The minor forms of P-450LM have proved difficult to purify, especially in large amounts. We plan to pursue this goal, however, with the aim of comparing the isozymes as to physical and chemical properties as well as substrate specificity. The substrates to be tested will include steroids and fatty acids as well as drugs, carcinogens, and other foreign compounds. One of our major efforts is the complete sequencing of P-450LM2 as well as of other forms of P-450LM, if funds and time permit, these studies are being carried out in collaboration with Dr. K.T. Yasunobu of the University of Hawaii. We have begun some studies on the m-RNA involved in LM2 synthesis in the hope we can use nucleic acid sequencing techniques as an aid to the difficult problem of amino acid sequencing of hydrophobic, poorly soluble peptides.